How does Sandy handle web addresses?

This is a really minor situation, but since it seems to be something set up to work, I figured I'd ask about it.

I've looked through Sandy's help documentation, but I can't figure out how to associate a web address with an item, aside from editing the item after she's already got the request. I experimented a couple of times but couldn't figure out how to get it to work.

Also, regarding that "URL" field I get when editing an item...could it be tweaked so that the "http://" prefix is optional? When I try entering it without that part, she assumes it's a section of her own website (e.g., entering "www.google.com" makes Sandy give me a link that goes to "http://www.iwantsandy.com/www.google.com").